Preparation of Anion Exchanger from Bead-shaped Poly(vinyl alcohol)

Abstract

The previously reported poly (vinyl alcohol) beads were formalized and then etherified with epichlorohydrin or acetalized with bromoacetaldehyde diethyl acetal. Formalization and etherification have been performed to make crosslinking in the beads and to introduce halogen into the resin matrix, respectively. Bromoacetalization brings about simultaneous crosslinking and introducing of halogen. Strongly basic anion exchangers were obtained from the etherified or bromoacetalized poly (vinyl alcohol) beads prepared by the amination of them with trimethylamine, triethanolamine or N, N-diethyl-1, 3-propanediamine. The highest value of the total exchange capacity and the degree of swelling of strongly basic anion exchangers are approximately 2.4 meq/g and 40 ml/g, respectively. The exchangers contain quaternary, am monium groups as much as 20-100% on total exchange groups. Weakly basic anion exchangers were prepared from the above poly (vinyl alcohol) beads by amination of them with methylamine, ethylenediamine, diethylenetriamine, triethylenetetramine or tetraethylenepentamine. The highest value of the anion exchange capacity and the degree of swelling of weakly basic anion exchangers are approximately 7.0 meq/g and 24 ml/g, respectively. The bead-shaped anion exchangers obtained are moderately resistant to alkali or acid.